In entrained flow gasification, the input material to be gasified, such as coal dust, is stored in what is known as the supply system, is tensioned to the required operating pressure of between 2.5 MPa and 8 MPa and is fed to the burner via delivery lines. Here, the rapid pressure increase of the fuel dust to operating pressure in what is known as the lock container represents a special problem. The pressure increase takes place by way of the addition of N2 or CO2 as tensioning medium. Said tensioning operation can lead to solidification of the fuel dust bed if the tensioning medium is fed in exclusively from the top of the lock. A solidification of this type is to be avoided if possible for disruption-free discharge of the fuel dust.
In order to avoid a solidification of the fuel dust bed in the lock as a result of the tensioning operation, a part flow of the gas which is required for the tensioning operation can be fed in in the discharge region of the container. Discharging aids, as are used as standard in silo technology in the form of, for example, aeration pads or vibration pads, are unsuitable for this purpose. Said elements are designed for non-pressurized environments and are not subjected to any relatively great alternating pressure and/or temperature stresses.
The prior art is a fluidizing element, as described in document WO 2006/064014 A1. This solution has the disadvantage that said element is complicated to manufacture, consists of a plurality of individual parts and leads to higher weights on account of a double flange connection with a relatively large diameter, and is difficult to handle for assembly at the building site. Furthermore, there is the disadvantage that the spacing between the isolation valve and the lock outlet and between the isolation valve and the fluidizing area is correspondingly increased on account of the design and therefore the supply system is of higher overall design, but there is also the risk of a solidification of the dust between the isolation valve and the fluidizing area. In addition, it has been shown in practice that relatively high speeds and differential pressures which result therefrom over the fluidizing area are necessary. They cannot be achieved by way of the solution which is described in WO 2006/064014 because the mechanical stability cannot be achieved solely by way of the filter material.